Keyhole illuminating devices are well known in the art. Typical of the patents showing such devices, in which the positive battery terminal is held away from the bulb terminal by a helical compression spring and the battery is bodily moved to engage the bulb, is U.S. Pat. No. 2,765,396. Other patents directed to keyhole illuminating devices are U.S. Pat. Nos. 2,699,490 and 2,732,480.
The apparatus of the present invention represents an improvement over prior moveable-battery type devices in that it utilizes a one-piece molded barrel or housing, the junctional area between the moveable switch button or pin and the housing is weather proof, and a thin conductive strap extending the length of the battery provides electrical continuity to the bulb. Further, the curved nose assembly and a retainer disc, adjacent the end of the battery, keeps the bulb and spring centered in the bore of the housing. A minimum number of economically formed and assembled component parts characterizes the apparatus and the result is a device having a long, service-free, operating life.